The effect of a thin layer of hexapropyltruxene inserted at the interface between the electron donor boron subphthalocyanine chloride (SubPc) and its underlying hole contact in planar heterojunction solar cells was investigated.

An organic semiconductor, expressed as a quadrupolar linear conjugated system (DPP Linear-c), consisting of a 1,4-diketopyrrolo[3,4-c]pyrrole (DPP) central unit and two quaterfluorenylphenyl arms at the 3- and 6-positions of the DPP fragment, is studied in organic field-effect transistors (OFETs). The strong propensity of DPP Linear-c to aggregate in the solid state favours the hole mobility of the semi-conductor due to the alignment of HOMOs in the aggregates. The fabrication of OFETs from this novel p-type semiconductor is reported, using different dielectrics to evaluate their effect on the overall device performance. Despite its aggregation, DPP Linear-c remains luminescent in the solid state. Electroluminescence of a non-optimised OLED fabricated from this material is demonstrated.

The platinum-based chemotherapeutic drug cisplatin is highly effective in the treatment of solid tumours, but its use is restricted by poor bioavailability, severe dose-limiting side effects and rapid development of drug resistance. In light of this we have tethered the active component of cisplatin to gold-coated iron oxide nanoparticles to improve its delivery to tumours and increase its efficacy. Iron oxide nanoparticles (FeNPs) were synthesised via a co-precipitation method before gold was reduced onto the surface (Au@FeNPs). Aquated cisplatin was used to attach {Pt(NH3)(2)} to the nanoparticles by a thiolated polyethylene glycol linker forming the desired product (Pt@Au@FeNP). The nanoparticles were characterised by dynamic light scattering, scanning transmission electron microscopy, UV-Vis spectrophotometry, inductively coupled plasma mass spectrometry and electron probe microanalysis. The nanoparticles increase in size as they are constructed, with the synthesised FeNPs having a diameter of 5-50 nm, which increases to 20-80 nm for the Au@FeNPs, and to 60-120 nm for the Pt@Au@FeNPs. Nanoparticle drug loading was found to be 7.9 x 10(-4) moles of platinum per gram of gold. The FeNPs appear to have little inherent cytotoxicity, whereas the Au@FeNPs are as active as cisplatin in the A2780 and A2780/cp70 cancer cell lines. More importantly the Pt@Au@FeNPs are up to 110-fold more cytotoxic than cisplatin. Finally, external magnets were used to demonstrate that the nanoparticles could be accumulated in specific regions and that cell growth inhibition was localised to those areas. (C) 2012 Elsevier B.V. All rights reserved.